7824 Orbital Lymphoma masquerading as Thyroid Eye Disease

Abstract

Abstract Disclosure: S. Ganawa: None. S. Joseph: None. C. Anshuman: None. D. Luciane L: None. A. Sajid: None. C. Anne: None. S. Dhage: None. Thyroid eye disease (TED) is the most common extrathyroidal manifestation in Graves’ disease (GD). In this case report, we present a case of a 64 years old lady, who was initially diagnosed with thyroid eye disease about 9 years ago. However, she was clinically and biochemically euthyroid. She was offered an orbital decompression surgery by local ophthalmology team. Patient wasn’t keen on the surgery at this stage.Recently she experienced increased swelling of her eyes, with conjunctival redness, oedema, and diplopia bilaterally, more evident on the left side. She was initiated on intravenous methylprednisolone (IVMP) weekly, by local ophthalmology team and was referred to our specialist thyroid eye clinic for further management.On presentation to us, her clinical activity score (CAS) was 5/7, but she was euthyroid clinically and biochemically. She was continued on weekly IVMP and oral mycophenolate mofetil (MMF) was added on as per the latest EUGOGO guidelines published in 2021. Her treatment was reviewed after the anti thyroperoxidase (TPO) and anti-Thyroid Stimulating Hormone receptor (TSH) antibodies were reported as negative and her eyes worsened despite the treatment with IVMP and MMF.Her repeat MR orbit at this stage showed possible orbital lymphoma. Her immunosuppressive medications were discontinued at this stage. After further discussions at regional thyroid eye MDT and radiology MDT, an orbital biopsy was arranged for, which confirmed Extra nodal Marginal Zone lymphoma, with no high-grade component. She has been referred to the oncology unit for further assessment and management.This case highlights the importance of considering alternative differential diagnosis in certain patients with atypical features or those who are non-responders to the first line immunosuppressive therapies for thyroid eye disease. Details of this case and relevant literature will be reviewed in this report. Presentation: 6/3/2024